virtio-ccw: enable virtio-1

Let's enable revision 1 for virtio-ccw devices. We can always offer
VERSION_1 as drivers in legacy mode won't be able to see it anyway.

We have to introduce a way to set a lower maximum revision for a device
to accommodate the following cases:
- compat machines (to enforce legacy only)
- virtio-blk with scsi support (version 1 + scsi is fenced by common
  code, with a user-configured max revision of 0 we can allow scsi
  via not offering VERSION_1)

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

1 files changed, 4 insertions, 2 deletions

diff --git a/hw/s390x/virtio-ccw.h b/hw/s390x/virtio-ccw.h
index 692ddd7318..7ab8367baa 100644
--- a/hw/s390x/virtio-ccw.h
+++ b/hw/s390x/virtio-ccw.h
@@ -88,6 +88,7 @@ struct VirtioCcwDevice {
     SubchDev *sch;
     char *bus_id;
     int revision;
+    uint32_t max_rev;
     VirtioBusState bus;
     bool ioeventfd_started;
     bool ioeventfd_disabled;
@@ -102,9 +103,10 @@ struct VirtioCcwDevice {
 };
 
 /* The maximum virtio revision we support. */
-static inline int virtio_ccw_rev_max(VirtIODevice *vdev)
+#define VIRTIO_CCW_MAX_REV 1
+static inline int virtio_ccw_rev_max(VirtioCcwDevice *dev)
 {
-    return 0;
+    return dev->max_rev;
 }
 
 /* virtual css bus type */